Bewilderingly, it actually brings to mind for me part of the historical romanization of Gamilaraay; they used to romanize the voiced velar nasal /ŋ/ (like the “ng” in “sing”) with a capital G that was rotated one hundred eighty degrees (or π/2 radians, if you prefer), as below:
http://en.wikipedia.org/wiki/File:Ngummi.png
(Had to repost because greater-/less-than signs, which represent orthographic/romanization sequences in linguistics, just get converted into HTML on the board.)
Abstract 
Robert Quick